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Determination of t8/5 cooling times for underwater local dry welding of steel
PublikacjaKnowledge of thermal history is the basic condition for studying the structure - properties of welded joints. The determinant of thermal history is the thermal cycle, whose in-situ measurements are still a big challenge. Water as the welding environment complicates this issue even more. The article presents a method to determine an equation for calculating t8/5 cooling times for underwater gas metal arc welding of unalloyed steels...
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Rapid Design of 3D Reflectarray Antennas by Inverse Surrogate Modeling and Regularization
PublikacjaReflectarrays (RAs) exhibit important advantages over conventional antenna arrays, especially in terms of realizing pencil-beam patterns without the employment of the feeding networks. Unfortunately, microstrip RA implementations feature narrow bandwidths, and are severely affected by losses. A considerably improved performance can be achieved for RAs involving grounded dielectric layers, which are also easy to manufacture using...
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Potential Impact of Waterway Development on Cultural Landscape Values: The Case of the Lower Vistula
PublikacjaThe northern (“lower”) section of the Vistula is on the route of two international waterways—E70 and E40. However, the current condition of the riverbed prevents larger vessels from passing through. Plans for the waterway date back to the beginning of the 20th century. Following Poland’s ratification of the European Agreement on Main Inland Waterways of International Importance in 2017, the general concept has been transformed...
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Molecular Strategy for Survival at a Critical High Temperature in Eschierichia coli
PublikacjaThe molecular mechanism supporting survival at a critical high temperature (CHT) in Escherichia coli was investigated. Genome-wide screening with a single-gene knockout library provided a list of genes indispensable for growth at 47°C, called thermotolerant genes. Genes for which expression was affected by exposure to CHT were identified by DNA chip analysis. Unexpectedly, the former contents did not overlap with the latter except...
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THREE-DIMENSIONAL numerical investigation of MHD nanofluid convective heat transfer inside a CUBIC porous container with corrugated bottom wall
PublikacjaSimultaneous use of porous media and nanofluid as a heat transfer improvement method has recently captivated a great deal of attention. The heat transfer and entropy production of the Cu-water nanofluid inside a cubic container with a heated bottom wavy wall and an elliptic inner cylinder were numerically analyzed in this study. The container is partitioned into two sections: the left side is filled with permeable media and...
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Materiały do poznania ważek (Odonata) Pojezierza Litewskiego (Polska północno-wschodnia), ze szczególnym uwzględnieniem Suwalskiego Parku Krajobrazowego, zebrane przy okazji XIX Sympozjum Sekcji Odonatologicznej Polskiego Towarzystwa Entomologicznego w 2023 r.
PublikacjaFrom 6-9 July 2023, the participants of the 19th Symposium of the Odonatological Section of the Polish Entomological Society carried out fieldwork on the dragonflies in and around the Suwałki Landscape Park (SPK) (NE Poland). The symposium was preceded by a field reconnaissance (8-10 June). The results of this fieldwork, which yielded 45 species at 22 sites, are presented and discussed. Three species...
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Just Let Me Think: Designing Against Acquired Illiteracy.
PublikacjaThis article concerns the relatively new problem of illiteracy relating to persons previously being literate, which is caused by too intensive using of so-called digital media (TV, computers, tablets, smartphones, e-book readers, portable media players, etc.). The problem has been observed for several years mainly in countries with high economic and technological development. The widespread use of digital media and the ease of...
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Technology convergence and digital divides. A country-level evidence for the period 2000–2010
PublikacjaThe paper, mostly empirical in nature, investigates issues on cross-national new information and communication technologies (ICTs) adoption patterns and growth directions. In the period of 2000–2010, a great number of countries underwent substantial changes on the field of ICTs implementation. Many of them made a great “jump” starting with almost “zero level” of ICTs adoption in the year 2000 and during the ten- year period were...
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Compatibility of Crude Oil Blends─Processing Issues Related to Asphaltene Precipitation, Methods of Instability Prediction─A Review
PublikacjaProcessing crude oil of variable composition, especially due to the need to process crude oil blends obtained from various sources, presents a tremendous process challenge. This is mainly due to the destabilization of the colloidal system manifested mostly by the precipitation of the asphaltene fraction. The precipitation of asphaltenes from crude oil is a serious problem during extraction, transport, and processing. In the latter...
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Novel Versatile Topologies and Design Optimization of Wide-Bandstop Frequency Selective Surfaces for X-Band, Ku-Band and Millimeter-Wave Applications
PublikacjaNovel designs of frequency selective surface (FSS) are presented for wideband applications in X, Ku and mmWave (millimeter Wave) bands. Two identical metallic layers of FSS are imprinted on both sides of the RO4003 substrate. The geometry parameters are optimized to maximize the bandstop at the specified in-band maximum transmission level of –10 dB; satisfaction of the latter condition is enforced through appropriate formulation...
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Performance of Vector-valued Intensity Measures for Estimating Residual Drift of Steel MRFs with Viscous Dampers
PublikacjaViscous Dampers (VDs) are widely used as passive energy dissipation system for improving seismic performance levels especially in retrofitting of buildings. Residual Inter-story Drift Ratio (R-IDR) is another important factor that specifies the condition of building after earthquake. The values of R-IDR illustrates the possibility of retrofitting and repairing of a building. Therefore, this study aims to explore the vector-valued...
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Re-use of historic wooden verandas in Sopot, Poland
PublikacjaSopot is the best-known seaside resort in Poland. The city is unique with regard not only to its location and natural values, but also its interesting architecture, which dates back to the end of the 19th and the beginning of the 20th century. Wooden verandas are one of the characteristic features of Sopot architecture. Their origin is associated with the Swiss style, which was fashionable at the turn of the 20th century and quite...
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A method to monitor urinary carbon dioxide in patients with septic shock
PublikacjaSevere sepsis and septic shock are life-threatening conditions with mortality rates exceeding 31% (Levy et al., 2012) [1]. Septicemia was the most expensive US hospital condition in 2011 (Torio and Andrews, 2006)[2]. Urinary carbon dioxide may provide rapid, clinically useful information about a patient’s status, empowering physicians to intervene earlier and improve septic shock mortality. The objective of this paper is to validate...
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Factors determining accumulation of bisphenol A and alkylphenols at a low trophic level as exemplified by mussels Mytilus trossulus
PublikacjaThe aim of the study was to investigate abiotic and biotic factors influencing the accumulation of endocrine disrupting compounds (EDCs) such as bisphenol A (BPA), 4-tert-octylphenol (OP) and 4- nonylphenol (NP) in mussels Mytilus trossulus from the Gulf of Gdansk (Southern Baltic). The key abiotic factor influencing BPA, OP and NP accumulation in mussels is their hydrophilicity/lipophilicity, which affects their main assimilation...
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Reinforced concrete thin wall dome after eighty years of operation in maritime climate environment
PublikacjaThe paper presents a description of the construction elements of the Gdynia Seaport main hall dome. Firstly, it provides information about the technical condition of the dome’s structure. Secondly, it examines the strength analysis of the thin-walled reinforced concrete dome covering. Throughout the last 80 years the building has been exposed to an unfavourable marine climate. The analysis of the state of stress and deformations...
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Siedmiokryterialny miernik oceny niepotokowych procesów produkcyjnych
PublikacjaGrowing expectations of clients, who demand products adapted to their individual needs is inducing the development of batch processes. The author developed a model of batch processes rating based on the following criterions: • Economical criterion applies to evaluation of the productions’ cost levels connected with the process subjected to analysis and necessary investment funds. • Ecological criterion is about means of natural...
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EVALUATION OF EFFECTIVENESS OF WATERJET PROPULSOR FOR A SMALL UNDERWATER VEHICLE
PublikacjaT he goal of the project described is to replace the existing propulsion system of a small underwater vehicle with a solution less prone to mechanical damage and ensuring a lower risk of the entanglement of fibrous objects suspended in the body of water. Four typical marine screws are utilised in the current design of the vehicle. One possible solution of the problem is the application of waterjet propulsors located...
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SPECTRAL RESPONSE OF STATIONARY JACK-UP PLATFORMS LOADED BY SEA WAVES AND WIND USING PERTURBATION METHOD
PublikacjaThe paper addresses non-linear vibrations of offshore jack-up drilling platforms loaded by sea waves and wind in their stationary condition using the perturbation method. Non-linearity of dynamic equations of motion for fixed offshore platforms yields from two factors. The first is load excitation generating non-linear velocity coupling in a dynamic system. This coupling is inherent in the modified Morison equation, involving the...
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Electrical Tree Growth Behavior Under AC and DC High Voltage in Power Cables
PublikacjaThis work investigates the impact of an applied AC and DC high voltage on the electrical tree behavior in extruded cross-linked polyethylene (XLPE) insulation based on simulation and experimental validation. Extensive partial discharge (PD) testing methods are being implemented for high voltage cables under AC voltage for monitoring their condition. However, these PD testing methods cannot be utilized for power cables under DC...
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Thermo-Mechanical Simulation of Underwater Friction Stir Welding of Low Carbon Steel
PublikacjaThis article investigates the flow of materials and weld formation during underwater friction stir welding (UFSW) of low carbon steel. A thermo-mechanical model is used to understand the relation between frictional heat phenomena during the welding and weld properties. To better understand the effects of the water environment, the simulation and experimental results were compared with the sample prepared by the traditional friction...
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Landscape as a Potential Key Concept in Urban Environmental Planning: The Case of Poland
PublikacjaRapid urban development increases the consumption of materials, energy, and water, resulting in an overproduction of waste and emissions. These cause many environmental threats, such as ozone layer depletion and rain acidification, leading to climate change. Therefore, the question arises on how to improve the effectiveness of tools that strengthen environmental protection. This discursive article presents an approach stressing...
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Analysis of electricity generation variability in 2019 with special consideration of electrical energy generation from wind sources.
PublikacjaThis article presents issues related to the broadly understood development of wind energy. The state of the art of wind energy in the world has been discussed. This paper also shows issues related to factors affecting the development of renewable energy sources and their impact on the natural environment on the basis of available research. The focus is, however, on the critical analysis of phenomena in the data of the Transmission...
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Characterization of Defects Inside the Cable Dielectric With Partial Discharge Modeling
PublikacjaThe continuous monitoring of power system devices is an important step toward keeping such capital assets safe. Partial discharge (PD)-based measurement tools provide a reliable and accurate condition assessment of power system insulations. It is very common that voids or cavities exist in every solid dielectric insulation medium. In this article, different voids are modeled and analyzed using an advanced finite element (FE)-based...
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Wavelet Transform Analysis of Heart Rate to Assess Recovery Time for Long Distance Runners
PublikacjaThe diagnostics of the condition of athletes has become a field of special scientific interest and activity. The aim of this study was to verify the effect of a long (100 km) run on a group of runners, as well as to assess the recovery time that is required for them to return to the pre-run state. The heart rate (HR) data presented were collected the day before the extreme physical effort, on the same day as, but after, the physical...
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Probabilistic analysis of settlements under a pile foundation of a road bridge pylon
PublikacjaThe paper addresses the reliability change of a road bridge pile foundation due to the unpredictable increase of settlements in time. The analysis is based on the Rędziński Bridge in Wrocław, Poland, its design assumptions, and monitoring results. The bridge foundation rests on a multi-layered subsoil assumed random. The Finite Element model of the subgrade is generated in ZSoil® software. To simplify the probabilistic approach,...
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THE RISE OF FISCAL OPACITY IN POLAND IN THE ERA OF THE COVID-19 PANDEMIC
PublikacjaResearch background: The quality of information provided by the fiscal authorities and the correct flow of this information between them and the society are very important especially in times of crisis, when there is an imbalance in public finances and an increasing public debt. Ensuring fiscal transparency (transparency of public finances) reduces fiscal risk and corruption and supports public acceptance of fiscal reforms. Purpose...
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Expert System and Decision Support System for Electrocardiogram Interpretation and Diagnosis: Review, Challenges and Research Directions
PublikacjaElectrocardiography (ECG) is one of the most widely used recordings in clinical medicine. ECG deals with the recording of electrical activity that is generated by the heart through the surface of the body. The electrical activity generated by the heart is measured using electrodes that are attached to the body surface. The use of ECG in the diagnosis and management of cardiovascular disease (CVD) has been in existence for over...
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Assessment of Environmental Loads in the Life Cycle of a Retail and Service Building
PublikacjaIn order to achieve the European Union’s climate and energy goals, investments are required, mainly in the areas of energy efficiency, renewable energy sources and infrastructure. Buildings are responsible for almost half of total energy consumption, and nearly 80% of them are energy and ecologically inefficient. The policy of European countries is increasingly more focused on facilities with the highest potential in the areas...
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Koncepcja analizy stanów emocjonalnych użytkowników w kontekście systemów zabezpieczeń transportowych
PublikacjaAutorzy, przywołując własne i światowe badania nad rozpoznawaniem emocji ludzkich z obrazu twarzy, wskazują na możliwość zastosowania algorytmów komputerowych i ich implementacji w komputerach osobistych (i innych urządzeniach personalnych wyposażonych w dostatecznie silny procesor obliczeniowy). Zastosowanie takiego rozwiązania może poprawić bezpieczeństwo użytkowania urządzeń, maszyn i pojazdów, których operatorzy muszą gwarantować...
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Transport of Particles in Intestinal Mucus under Simulated Infant and Adult Physiological Conditions: Impact of Mucus Structure and Extracellular DNA
PublikacjaThe final boundary between digested food and the cells that take up nutrients in the small intestine is a protective layer of mucus. In this work, the microstructural organization and permeability of the intestinal mucus have been determined under conditions simulating those of infant and adult human small intestines. As a model, we used the mucus from the proximal (jejunal) small intestines of piglets and adult pigs. Confocal...
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Globalized Knowledge-Based Simulation-Driven Antenna Miniaturization Using Domain-Confined Surrogates and Dimensionality Reduction
PublikacjaDesign of contemporary antenna systems encounters multifold challenges, one of which is a limited size. Compact antennas are indispensable for the new fields of application such as inter-net of things or 5G/6G mobile communication. Still, miniaturization generally undermines elec-trical and field performance. When attempted through numerical optimization, it turns into a constrained problem with costly constraints requiring electromagnetic...
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Globalized Simulation-Driven Miniaturization of Microwave Circuits by Means of Dimensionality-Reduced Constrained Surrogates
PublikacjaSmall size has become a crucial prerequisite in the design of modern microwave components. Miniaturized devices are essential for a number of application areas, including wireless communications, 5G/6G technology, wearable devices, or the internet of things. Notwithstanding, size reduction generally degrades the electrical performance of microwave systems. Therefore, trade-off solutions have to be sought that represent acceptable...
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The effective elastic properties of human trabecular bone may be approximated using micro-finite element analyses of embedded volume elements.
PublikacjaBoundary conditions (BCs) and sample size affect the measured elastic properties of cancellous bone. Samples too small to be representative appear stiffer under kinematic uniform BCs (KUBCs) than under periodicity-compatible mixed uniform BCs (PMUBCs). To avoid those effects, we propose to determine the effective properties of trabecular bone using an embedded configuration. Cubic samples of various sizes (2.63, 5.29, 7.96, 10.58...
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Analysis of the Water Level Variation in the Polish Part of the Vistula Lagoon (Baltic Sea) and Estimation of Water Inflow and Outflow Transport through the Strait of Baltiysk in the Years 2008–2017
PublikacjaThe Vistula Lagoon is located in both Poland and Russia along the southern coast of the Baltic Sea. It is connected to the Baltic Sea in the Russian part by the Strait of Baltiysk. The purpose of the paper is to identify the dominant factors underlying the water level variation mechanism at Tolkmicko in the Vistula Lagoon, revealed by a statistical analysis of the measured data and a discussion on the inflow and outflow transport...
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Experimental and computational study on mechanical behaviour of carpentry corner log joints
PublikacjaThis work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex...
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The ONETEP linear-scaling density functional theory program
PublikacjaWe present an overview of the ONETEP program for linear-scaling density functional theory (DFT) calculations with large basis set (planewave) accuracy on parallel computers. The DFT energy is computed from the density matrix, which is constructed from spatially localized orbitals we call Non-orthogonal Generalized Wannier Functions (NGWFs), expressed in terms of periodic sinc (psinc) functions. During the calculation, both the...
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The application of non-destructive methods in the diagnostics of the approach pavement at the bridges
PublikacjaThe article presents the possibility of using non-destructive methods of road pavement diagnostics as an alternative to traditional means to assess the reasons for premature cracks adjacent to bridge objects. Two scanning methods were used: laser scanning to measure geometric surface deformation and ground penetrating radar (GPR) inspection to assess the road pavement condition. With the use of a laser scanner, an effective tool...
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Analysis of pavement structure sensitivity to passage of oversized heavy duty vehicle in terms of bearing capacity
PublikacjaOversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor...
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Influence of the Spectral Quality of Light on Daytime Alertness Levels in Humans
PublikacjaExposure to light is very important for human health. However, the characteristics of the light stimulus and the appropriate timing of such exposure are essential. Studies that have used monochromatic light exposure have shown no systematic patterns for the effects of blue light compared to longer wavelengths. Previous studies have shown that red light exposure increases objective and subjective measures of alertness at night without...
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Effect of pavement roughness and vehicle dynamic loads on decrease of fatigue life of flexible pavements
PublikacjaDue to the fact that pavement surfaces are not ideally even, dynamic loads of vehicle axles deviate from static loads. Higher dynamic loads contribute to faster pavement distress. The distribution of dynamic loads is similar to normal distribution and can be described by static load and factors DI (dynamic impact) and DLC (dynamic load coefficient). With the deterioration of pavement condition its evenness decreases as well and...
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Microbial diversity of inflamed and noninflamed gut biopsy tissues in inflammatory bowel disease.
PublikacjaBACKGROUND: Inflammatory bowel disease (IBD) is a chronic gastrointestinal condition without any known cause or cure. An imbalance in normal gut biota has been identified as an important factor in the inflammatory process. METHODS: Fifty-eight biopsies from Crohn's disease (CD, n = 10), ulcerative colitis (UC, n = 15), and healthy controls (n = 16) were taken from a population-based case-control study. Automated ribosomal intergenic...
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Multi-region fuzzy logic controller with local PID controllers for U-tube steam generator in nuclear power plant
PublikacjaIn the paper, analysis of multi-region fuzzy logic controller with local PID controllers for steam generator of pressurized water reactor (PWR) working in wide range of thermal power changes is presented. The U-tube steam generator has a nonlinear dynamics depending on thermal power transferred from coolant of the primary loop of the PWR plant. Control of water level in the steam generator conducted by a traditional PID controller...
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Nonlinear control of five phase induction motor with synchronized third harmonic flux injection
PublikacjaThe paper deals with the novel control system for five phase induction motor (IM) that enables the injection of the rotor flux 3rd harmonic component. Two multiscalar models are transformed from the 1-1 and 2-2 vector models developed in the 1st and 3rd harmonic planes. Based on the obtained multiscalar models the synthesis of dual multiscalar control is established. The obtained two multiscalar control systems can independently...
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Microbiota-derived metabolites in colorectal cancer patients in preoperative period
PublikacjaShort-chain fat-ty acids (SCFAs) are microbial derived metabo-lites, which have multiple beneficial properties. The amount of SCFAs depends on several fac-tors, such as age, diet (mainly intake of dietary fiber), and overall health condition. The normal proportion between SCFAs is 3:1:1 for acetate, proprionate and butyrate, respectively. In col-orectal cancer (CRC) patients, microbiota alter-ations have been shown. Consequently,...
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Expermental investigation on adsorption of methylene blue dye from waste water using corncob cellulose-based hydrogel
PublikacjaHydrogel from corncob cellulose was synthesized in this investigation. The synthesized Hydrogel was characterized by SEM, XRD, and FTIR instruments. As the results indicate the synthesized hydrogel has required and important features, these suggest the suitability of hydrogel for the adsorption of methylene blue dye (MBD). Three important process variables (dosage, contact time, and initial concentration) with three levels were...
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The experimental and numerical investigation of fracture behaviour in PMMA notched specimens under biaxial loading conditions – Tension with torsion
PublikacjaThis paper presents the results of experimental fracture test of flat PMMA specimens under biaxial loading condition tension with torsion (proportional). The specimens were made in two thicknesses: 5 and 15 mm and were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. Thanks to the ARAMIS 3D 4 M non-contact vision system, measurement of the elongation and twist angle were recorded. During experimental...
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Review on mechanisms and efficiency of removal of microbiological contaminants in constructed wetlands
PublikacjaConstructed wetlands (CW) have been considered as a waste and a stormwater treatment systems for small communities or for areas with unsteady sewage flow conditions. Several investigations were undertaken for estimation suspended solids, organic matter and nutrients efficiency removal but only few focused on retention of microorganisms in constructed wetlands. In this review mechanisms of elimination of viruses, indicator bacteria...
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FURTHER REMARKS ON THE NEO-CLASSICAL NAVIER-STOKES EQUATIONS
PublikacjaThe seminal Navier-Stokes equations have been stated yet before creation of principles of thermodynamics and the first and second laws. In the literature there is the common opinion that the Navier-Stokes equations cannot be taken as a thermodynamically correct model of “working fluid” which is able to describe transformation of “ heat” into “work” and vice versa. Therefore, in the paper, a new exposition of thermodynamically...
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Olfactory receptor-based biosensors as potential future tools in medical diagnosis
PublikacjaThe detection of biomarkers is the future of non-invasive medical diagnosis and screening. Discovery and identification of reliable disease specific volatile organic compounds is dependent on repeatable, accurate analysis of trace level gaseous analytes mainly in breath samples. Natural variety of the olfactory systems and the compounds capable of gas molecules binding creates wide possibilities of acquisition and implementation...
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Enhancing seismic performance of rigid and semi-rigid connections equipped with SMA bolts incorporating nonlinear soil-structure interaction
PublikacjaNowadays, using smart connections can improve the performance of buildings with some recentering features that are from the superelastic behavior of Shape Memory Alloys (SMAs). It seems that there is different rigidity between the designed connection and the real one in Steel Moment-Resisting Frames (SMRFs), which can be considered as a problematic issue due to the importance of connections in seismic performance assessment. This...